Combined analyses of deep tow magnetic anomalies and International Ocean Discovery Program Expedition 349 cores show that initial seafloor spreading started around 33 Ma in the northeastern South China Sea (SCS), but varied slightly by 1-2 Myr along the northern continent-ocean boundary (COB). A southward ridge jump of 20 km occurred around 23.6 Ma in the East Subbasin; this timing also slightly varied along the ridge and was coeval to the onset of seafloor spreading in the Southwest Subbasin, which propagated for about 400 km southwestward from 23.6 to 21.5 Ma. The terminal age of seafloor spreading is 15 Ma in the East Subbasin and 16 Ma in the Southwest Subbasin. The full spreading rate in the East Subbasin varied largely from 20 to 80 km/Myr, but mostly decreased with time except for the period between 26.0 Ma and the ridge jump (23.6 Ma), within which the rate was the fastest at 70 km/ Myr on average. The spreading rates are not correlated, in most cases, to magnetic anomaly amplitudes that reflect basement magnetization contrasts. Shipboard magnetic measurements reveal at least one magnetic reversal in the top 100 m of basaltic layers, in addition to large vertical intensity variations. These complexities are caused by late-stage lava flows that are magnetized in a different polarity from the primary basaltic layer emplaced during the main phase of crustal accretion. Deep tow magnetic modeling also reveals this smearing in basement magnetizations by incorporating a contamination coefficient of 0.5, which partly alleviates the problem of assuming a magnetic blocking model of constant thickness and

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Selective synthesis of lactic acid from bioderived substrates still remains a grand challenge. We reported a series of unique bimetallic Pt–Co/CeO x catalysts, prepared by fractional precipitation method. Strong electronic coupling for Pt–Co is found to enhance activity toward dehydrogenation (C–H bond cleavage) of glycerol, as evidenced from X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) studies of the catalysts. Detectable electroaffinity of PtCo trends to gain electrons from CeO x support; thus some side reactions (such as C–C and C–O bond cleavage) are largely restrained. Such hybridized structures lead to remarkable activity (turnover frequency (TOF) = 1533.9 h–1) with good selectivity toward lactic acid (87.7%) and total organic acids (>95%) at 200 °C. In addition, the effect of reaction temperature and substrate concentration on the initial reaction rate reveals that dehydrogenation of glycerol possibly follows a dual-site mechanism, where both glycerol and base need to be activated on the bimetallic Pt–Co surface. Furthermore, the plausible reaction pathway is discussed in detail.

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